/* -*- mode: C -*-  */
/* 
   IGraph library.
   Copyright (C) 2013  Gabor Csardi <csardi.gabor@gmail.com>
   334 Harvard st, Cambridge MA, 02139 USA
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc.,  51 Franklin Street, Fifth Floor, Boston, MA 
   02110-1301 USA

*/

#include <igraph.h>
#include <stdio.h>

int main() {

  igraph_t star, ring, uni, result;
  igraph_vector_ptr_t glist;

  igraph_star(&star, 11, IGRAPH_STAR_UNDIRECTED, /*center=*/ 10);
  igraph_ring(&ring, 10, IGRAPH_UNDIRECTED, /*mutual=*/ 0, /*circular=*/ 1);
  
  igraph_union(&uni, &star, &ring, /*edge_map1=*/ 0, /*edge_map2=*/ 0);
  
  igraph_intersection(&result, &uni, &star, /*edge_map1*/ 0, 
		      /*edge_map2=*/ 0);
  igraph_write_graph_edgelist(&result, stdout);

  igraph_destroy(&result);

  /* ---------------------------- */
  
  igraph_vector_ptr_init(&glist, 2);
  VECTOR(glist)[0] = &uni;
  VECTOR(glist)[1] = &star;
  
  igraph_intersection_many(&result, &glist, /*edgemaps=*/ 0);
  printf("--\n"); igraph_write_graph_edgelist(&result, stdout);

  igraph_vector_ptr_destroy(&glist);
  igraph_destroy(&result);
  igraph_destroy(&uni);
  igraph_destroy(&ring);
  igraph_destroy(&star);
  
  return 0;
}
